AVS 49th International Symposium
    Vacuum Technology Tuesday Sessions
       Session VT-TuM

Paper VT-TuM1
Expanded Characteristics Evaluation for Low Vacuum Dry Pumps

Tuesday, November 5, 2002, 8:20 am, Room C-104

Session: Novel Vacuum Materials and Pumps, Including Getters
Presenter: J.Y. Lim, Korea Research Institute of Standards and Science
Authors: J.Y. Lim, Korea Research Institute of Standards and Science
S.H. Chung, Korea Research Institute of Standards and Science
W.S. Cheung, Korea Research Institute of Standards and Science
K.H. Chung, Korea Research Institute of Standards and Science
Y.H. Shin, Korea Research Institute of Standards and Science
S.S. Hong, Korea Research Institute of Standards and Science
W.G. Sim, Hannam University, Korea
Correspondent: Click to Email
Since positive-displacement dry pumps were first launched into the semiconductor industry in 1984, issues concerning about characteristics evaluation on consistent bases have been continuously arisen from the mass production lines. Besides their clean and continuous pumping capability, occasional devastating malfunctions or characteristic degradations of such pumps during the manufacturing processes have been also reported in the Korea semiconductor industry. On behalf of these issues, the integrated characteristics evaluation system for dry vacuum pumps has been developed collaborating with several semiconductor and branch dry pump manufacturers in Korea. The evaluation system exploits the constant volume flowmeter to measure the mass flow rate in standards level, and facilitates the evaluation of spatially averaged sound power levels using a reverberation chamber.@footnote 1@ New and overhauled roots, claw, classical screw, and scroll type pumps supplied from the manufacturers have been evaluated using the evaluation system in terms of ultimate pressure, pumping speed, vibration, and sound power. The correlation analyzed among those results shows clear signs of pump degradation related each other. We selected the mass flow measuring method with a constant chamber volume of 874 L because of its direct monitoring capability not allowing blind mass flow rate measurement, and proved the method allows us to measure five decades of mass flow rates from 0.01 to 10@super 3@ mbar-l/s with an uncertainty of ±3% which is within the internationally accepted standards limit. In this work the integrated characteristics evaluation method has been significant because of pump degradation or malfunction symptom to be further understood and predicted. @FootnoteText@ @footnote 1@W.S. Cheung, J.Y. Lim, K.H. Chung, Experimental study on noise characteristics of dry pumps, The 2002 International Congress and Exposition on Noise Control Engineering, Inter-noise 2002, Dearborn, MI, USA.